Hello, Can anyone tel me if a 1969 MK2 Cortina 1600 (Crossflow) will run on unleaded without adjustment? If not, What needs to be done to enable it. thanks in anticipation
Bill .
- posted
20 years ago
unleaded?
Loading thread data ...
- Vote on answer
- posted
20 years ago
It will run on unleaded for about 5000-10000 miles owing to the build up of lead deposits on the valve seats before you will probably experience valve seat wear. This is somethig called memory effect. The ignition timing may have to be retarded about 2 degrees to stop detonation (pinking).
Eventually hardened valve seats are required and maybe new valves to suit. Apparently you only need to do the inlet valves and seats. While your at it you might as well go for bigger valves. Local to me this would cost about £100 if you include valves.
It would be advantageous to source a good secondhand head and have the work done on that. Then it is only an afternoon off the road while the unleaded head is fitted.
Hope this helps, Dixie